The
trombone is a brass instrument with a fairly low pitch. It has a
cylindrical bore with a flared bell at the far end. It has a long, U-shaped tube
between the mouth-piece and the main tube, which can be slid in and out, to
lengthen or shorten the column of air,
thus lowering or raising the pitch of the
note produced. The sound is produced by vibrations of the player's lips
into the cup-shaped mouthpiece. When the lips are fairly slack, the low,
fundamental tone is sounded. As the lips are successively tightened, and the air
pressure is increased, the overtones of the harmonic series are generated
successively.

The slide is used to alter the pitch by semi-tone
intervals, thus filling in the gaps between the notes of the harmonic series.
This is equivalent to the valves on a trumpet or French horn, permitting the
full chromatic scale to be played. However, it takes some time to move the slide
from one position to another, so rapid passages cannot be played on this
instrument, unlike the trumpet. In jazz the slide is often used whilst continuously
sounding the instrument, generating a sliding pitch, or a glissando effect.

The
trombone was used in early music especially in operas. It then seems to have
been infrequently employed in orchestras until Beethoven's time and onward. It
is now a standard instrument of the modern symphony orchestra, and also in brass
bands, dance bands and jazz ensembles.

There are two types of trombone.
The bass trombone has a range from B1 (just below the C 2 octaves below middle
C) up to the F above middle C. The tenor goes from E2 (1� octaves below middle
C) up to Bb4 (Bb above middle C).

Music featuring the Trombone. Audio is available for 23 tunes for this instrument.